EP3287158B1 - Method and devices for testing at least one function of a medical functional device - Google Patents

Description

The present invention relates to a method according to claim 1. It also relates to a detection device according to claim 8 and a medical treatment device according to claim 12. The present invention also relates to a computer program product according to claim 14.

Machine tests for checking the function and reliability of medical functional devices such as extracorporeal blood tubes, blood cassettes and the like are known from practice (see e.g U.S. 2005/126998 ). Such a test is known as a pressure holding test. It is carried out after the functional device in question is connected to the treatment device, ie after the treatment device has already been upgraded with the functional device, and before the treatment of the patient begins.

One object of the present invention is to propose a further method for checking the function of medical functional devices. In addition, suitable devices and a suitable computer program product should be specified.

The object according to the invention is achieved by a method having the features of claim 1. It is also solved by means of the detection device with the features of Claim 8, the treatment device having the features of claim 12, and the computer program product having the features of claim 14.

According to the invention, a method is thus proposed for checking at least one function of a medical functional device while it is inserted into a medical treatment device and connected to it, in particular in fluid communication, and/or for checking a function of the treatment device connected to the functional device.

The method can include inserting the functional device into the medical treatment device, or at least requires this.

The method can also include pressing, prestressing or clamping the functional device in the treatment device, for example by means of the door of the treatment device. Alternatively, it assumes this.

Furthermore, the method can include establishing at least one fluid communication between a hydraulic device or a pneumatic unit of the treatment device and the functional device. Alternatively, this state is already present before the beginning of the procedure.

The method according to the invention includes building up a pressure by means of the hydraulic device or a pneumatic unit within the fluid communication. It includes in addition, a subsequent measurement of a pressure increase that can be determined after the pressure has built up within the fluid communication.

Furthermore, the method according to the invention includes making a statement about the checked function of the functional device on the basis of a comparison of the measured increase in pressure with previously stored values, threshold values, ranges or curves.

The detection device according to the invention is suitable and provided and/or designed and/or configured for carrying out the method according to the invention.

The medical or medical-technical treatment device according to the invention (hereinafter also abbreviated to: treatment device) has at least one detection device and/or is connected thereto in signal transmission or is in a signal-transmission relationship with it.

A computer program product according to the invention has a volatile program code or one stored on a machine-readable carrier for initiating the mechanical steps of the method according to the invention when the computer program product runs on the acquisition device according to the invention. According to the invention, a computer program product can be, for example, a computer program stored on a carrier, an embedded system as a comprehensive system with a computer program (e.g. electronic device with a computer program), a network of computer-implemented computer programs (e.g. client/server system, cloud computing system, etc.), or a computer on which a computer program is loaded, run, stored, executed or developed.

The term "machine-readable medium" as used herein means, in certain embodiments of the present invention, a medium containing data or information interpretable by software and/or hardware. The carrier can be a data medium such as a diskette, a CD, a DVD, a USB stick, a flash card, an SD card and the like.

In all of the following statements, the use of the expression "may be" or "may have" etc. is to be understood as synonymous with "is preferably" or "has preferably" etc. and is intended to explain an embodiment according to the invention. Advantageous further developments of the present invention are the subject matter of subclaims and embodiments.

Embodiments according to the invention can have one or more of the features mentioned below.

In some embodiments according to the invention, a predetermined waiting time or measurement time is awaited before a statement about the tested function is made.

A measurement of a pressure or a pressure change can include any kind of determination, for example a measurement by means of a sensor, a calculation, a conclusion based on numerical values of other parameters or circumstances, etc. Likewise, a determination as used herein, a check for the presence or Absence, measuring, "coming to a conclusion or statement", recognizing, ascertaining, or the like.

In some embodiments of the present invention, the facilities, devices, apparatus, and other items described herein include or are associated with the facilities, devices, apparatus, or other items required to perform method steps or test steps described herein.

In certain embodiments of the method according to the invention, the build-up of a pressure by means of the hydraulic device or the pneumatic unit within the fluid communication is only carried out if, with a previous application of a form which is lower than the pressure to be built up, no - or measured against a specification too high - Functional deviation was detected. A functional deviation that is too large is present, for example, if a leak is detected as soon as a form is applied.

In some embodiments according to the invention, the method includes filling, in particular complete filling, of the dialysate side and/or the blood side of a blood filter to which the functional device is connected in fluid communication.

In certain embodiments of the invention, the method includes building up the pressure using a substituate pump of the treatment device.

In some embodiments according to the invention, the method comprises building up the pressure against the substituate pump which is stationary or at most delivers in a defined manner.

In some embodiments of the invention, the method includes determining or measuring a pressure drop or a pressure increase within the fluid communication. It further includes that a continuity (or lack of continuity) of the fluid communication or the functional device is determined or postulated based on a comparison of the determined pressure drop or pressure increase with previously stored values, threshold values, ranges or curves.

In certain embodiments according to the invention, the method comprises determining or measuring a pressure drop or pressure increase—in particular within a predetermined period of time—within the fluid communication. It also includes determining (determining is also used or to be understood here synonymously with recognizing, postulating, etc.) of a tightness or a lack of tightness of the fluid communication or the functional device. This determination is based on a comparison of the determined pressure drop or pressure increase with previously stored values, threshold values, ranges or curves.

In certain embodiments of the present invention, the determination of a drop in pressure or a rise in pressure within the fluid communication occurs within a predetermined period of time.

In some embodiments according to the invention, the method comprises the delivery of a predetermined delivery volume within the fluid communication with the automatic substituate connector connected with or by means of a backwards-running substituate pump against a Check valve provided within a substituate channel. The method of these embodiments further includes detecting a pressure change within the fluid communication. It also includes determining a non-return function (or non-function) of the check valve in the event that a determined pressure drop is not equal to or greater than a maximum pressure drop. Alternatively, to check the non-return function, a pressure increase behind the non-return valve can of course also be monitored.

Under a reverse running pump, e.g. B. substituate pump, is to be understood as a pump which in a direction opposite to that direction (forward) promotes in which the considered pump during the treatment of the patient, at least predominantly promotes.

In some embodiments according to the invention, the method comprises the delivery of a predetermined delivery volume with the automatic substituate connector connected within the fluid communication with the substituate pump running backwards against a non-return valve which is provided within a substituate channel. It also includes detecting a pressure change within the fluid communication and determining that the substituate pump is advancing or has delivered if a detected pressure drop is greater than a maximum pressure drop.

wobei gilt:

WERT_neu

ist ein aktueller Druckwert, er kann ein fiktiver oder errechneter Wert sein;

WERT_alt

ist der bereits vorliegende oder zu einem früheren Zeitpunkt ermittelte Druckwert, er kann ebenfalls ein fiktiver oder - insbesondere mit der hier diskutierten Formel - errechneter Wert sein;

GF

ist ein Glättungsfaktor; und

MESSWERT

ist ein aktuell, also zum späteren, zweiten Zeitpunkt gemessener Druck.

In certain specific embodiments, the method according to the invention includes determining a current pressure value at a later, second point in time based on an already existing pressure value at an earlier, first point in time point in time, from a measured value and from a predetermined smoothing factor or multiplier - in particular during a pressure maintenance phase - according to the formula: $$\mathrm{WORTH}\_\mathrm{New}=\mathrm{WORTH}\_\mathrm{old}*\mathrm{GF}+\mathrm{MEASUREMENT}*\left(1-\mathrm{GF}\right)$$

where:

VALUE_new

is a current pressure value, it can be a fictitious or calculated value;

VALUE_old

is the pressure value that is already available or determined at an earlier point in time; it can also be a fictitious value or a calculated value, in particular using the formula discussed here;

GF

is a smoothing factor; and

MEASUREMENT

is a pressure measured currently, i.e. at a later, second point in time.

In certain embodiments of the method according to the invention, the smoothing factor is in a range from 0.9 to 0.96, in particular it corresponds to 0.93.

In some embodiments according to the invention, the method comprises the filling of an extracorporeal blood circuit connected to the functional device—preferably in such a way that it is free of air—before the pressure is built up.

In embodiments of the method according to the invention, at least one function, in particular the opening, the closing or a sealing function, of at least the valve for an addition point for substituate in pre-dilution; and a valve for an addition point for substituate in post-dilution. In addition, a function of a single-needle valve; a check valve in the substituate channel; and/or an automatic substituate connector.

In certain embodiments according to the invention, the method is carried out before starting treatment of a patient, in which case the functional device is used.

In certain embodiments according to the invention, the method comprises blocking treatment modalities and/or restricting treatment parameters of the treatment method or treatment modality. The blocking or restriction is based on (or including) a result of checking at least one function of the medical functional device and/or the treatment device by the present method.

In some embodiments of the method according to the invention, the medical functional device is a blood cassette and the treatment device is a blood treatment device.

In some embodiments according to the invention, the detection device has at least one display device for displaying a result of the implementation of the method according to the invention. The display device can be a display, an error display or the like.

In certain specific embodiments according to the invention, the detection device has at least one alarm device for outputting an alarm. The alarm device can be provided or configured to output an alarm in the event that the result of the implementation of the method according to the invention is not within a predetermined range or range of values. The alarm can be an audible and/or visual alarm.

In certain embodiments according to the invention, the detection device is programmed and/or configured in order to affect the treatment device in such a way that at least one treatment option or modality (e.g. a dialysis method, in particular as listed here), to which the checked functional device is intended or due to the design ( also) can be used, and/or the treatment under predetermined treatment parameters cannot be carried out using the specific, checked functional device. This applies in the event that a lack of functionality - e.g. B. insufficient closing, opening or sealing - the functional device and / or the treatment device (or a component thereof, in particular the valve of the addition point for substituate in pre-dilution and / or a valve of the addition point for substituate in post-dilution) was detected in this process .

In some embodiments, the detection device according to the invention acts on the treatment device in such a way that the treatment option(s) hemofiltration and/or hemodiafiltration cannot be carried out using the specific, tested functional device.

In some embodiments according to the present invention, the detection device is a control or regulation device and/or a function test monitor or has one(s) in each case.

In certain embodiments according to the invention, the medical treatment device is designed as a blood treatment device, in particular as a device for apheresis or dialysis, again in particular for hemodialysis, hemofiltration, hemodiafiltration.

Some or all embodiments of the invention may have one or more of the advantages mentioned above or below.

Thus, since safety-relevant functions of the articles used and of the treatment device are checked according to the invention, increased safety can be created for the patient.

Since the method according to the invention can take place during the preparation or upgrading of the treatment device, a technical error can already be detected before the patient is connected and before blood has come into contact with the treatment device and the extracorporeal blood circuit. The latter avoids unnecessary additional consumption of disposable items. It also allows a simple, early replacement of defective components in the event of a fault.

Since the method according to the invention can take place in some embodiments according to the invention without any action on the part of the staff on duty, but instead runs automatically, it is advantageously possible to detect errors in a work-time saving manner and even before treatment begins. In addition, the procedure described here, because it can be executed automatically, makes it possible for relevant test steps or procedures not to be forgotten.

Fig. 1

zeigt ein schematisch vereinfachtes Schaubild einer erfindungsgemäßen Behandlungsvorrichtung mit einer Blutkassette, welche mittels der vorliegenden Erfindung geprüft werden kann; und

Fig. 2

zeigt schematisch vereinfacht einen Pneumatik-Schaltplan einer erfindungsgemäßen Behandlungsvorrichtung.

The present invention is explained below by way of example with reference to the accompanying drawings, in which identical reference symbols denote the same or similar components. In the figures, some of which are greatly simplified, the following applies:

1

shows a schematically simplified diagram of a treatment device according to the invention with a blood cassette which can be checked by means of the present invention; and

2

shows schematically simplified a pneumatic circuit diagram of a treatment device according to the invention.

1 shows a diagram of a treatment device according to the invention with a blood cassette and its components, which are explained for a better understanding of the exemplary embodiments of the present invention explained below.

An extracorporeal blood circuit 1 runs outside and inside a blood cassette 2 and connects it to a treatment device 4. The extracorporeal blood circuit 1 has an access device (not shown), for example an arterial connection needle, on or connected to it. A fluid flow through the extracorporeal blood circuit 1 or sections thereof can be prevented by means of an arterial patient hose clamp 6, arranged in the patient's arterial hose 8 (also referred to as an arterial blood line), and also by means of a patient venous hose clamp 7 in the patient's venous hose 9 (also referred to as a venous blood line designated). A section of the extracorporeal blood circuit 1 is placed in a blood pump 11 . The extracorporeal blood circuit 1 has an addition point 13 for substituate liquid (in pre-dilution) and an addition point 14 for substituate liquid (in post-dilution). The addition points 13 and 14 or their valves are designed as phantom valves. Phantom valves of this type are in the WO 2010/121819 also described by the applicant of the present invention. For details, reference is made to that disclosure document.

An arterial air-blood detector 15 is provided on the arterial blood line 8 .

1 12 also shows a substituate pump 17. This is located downstream of a connection point at which the blood cassette 2 can be connected with its substituate port 18a to an automatic substituate connector 18b of the treatment device 4 before use. The automatic Substituatkonnektor 18b has in the example 1 a first fluid guide 3, a second fluid guide 5 and a third fluid guide 10 for flushing the automatic substituate connector 18b and for passing substituate through the automatic substituate connector 18b.

A blood filter 19 with a blood chamber 19a and a dialysate chamber 19b is connected into the extracorporeal blood circuit 1 .

The blood cassette 2 has a venous air separation chamber 21 .

A substituate line of the blood cassette 2 has a check valve 23 .

The extracorporeal blood circuit 1 has a venous air-substituate liquid-blood detector 25 on the venous blood line 9 .

The treatment device 4 has a compressed air source 26 or is connected to it. It also has a control or regulation device 28 or is connected to it.

In 1 a dialysis liquid inlet line 31a, which leads dialysis liquid to the dialysate chamber 19b, and a dialysate outlet line 31b, which carries dialysate away from the dialysate chamber 19b, can also be seen.

A pressure sensor 33a is provided in the arterial blood line 8 upstream of the blood pump 11 .

A pressure sensor 33b is provided in the area of the venous air separation chamber 21 in the venous blood line 9 .

A pressure sensor 33c, also referred to as a pre-filter pressure sensor, is provided downstream of the blood pump 11 in the arterial blood line 8 . This can be arranged upstream of the addition point 13 .

The blood cassette 2 has a single-needle valve 35 .

Another pressure sensor 37 is located in or on the dialysis fluid supply line 31a between the pressure source 26 and the blood filter 19.

Valves V 19 , V 24 , V 25 , V 28 , V 31 , V 32 , and V 33 are provided in hydraulic sections of the treatment device 4 .

The valve V24 is in or on the dialysis liquid supply line 31a.

The valve V25 is in or on the dialysate discharge line 31b.

The valve V28 is in a drain line 45.

The valve V31 is located in the first fluid line 3 of the automatic substituate connector 18b or in a line leading to it.

The valve V32 is in the second fluid line 5 of the automatic substituate connector 18b or in a line leading to it.

The valve V33 is in turn in the drain line 45.

Valve V19 is downstream of all of the above valves V24, V25, V28, V31, V32 and V33.

A hydraulic balance chamber 40 is only indicated.

2 shows a pneumatic circuit diagram of a treatment device according to the invention. Again, the components shown herein are provided to provide a better understanding of the exemplary embodiments of the present invention discussed below.

In 2 An air distributor plate 100 is shown which is connected to a pneumatic unit 200 . A single-needle unit 300 is also shown.

The air distributor plate 100 has connections to the feed point 13, to the feed point 14, to the single-needle valve 35, to a braking device 11' of the blood pump 11, to a braking device 17' of the substituate pump 17, and to other components not discussed further here.

The pneumatic unit 200 is used as a compressed air source 26 (see 1 ) connected to the hydraulics of the treatment device 4.

The single-needle unit 300 has a ventilation 301, a single-needle compressor 350, a bypass valve 352, a vent valve 354, a pressure sensor 356 on the single-needle pressure vessel, a pressure sensor 358 of the SN line, an absolute pressure sensor 360, and a temperature sensor 362 in the SN pressure vessel. A connector 370 connects the single-needle unit 300 to the single-needle chamber of the blood cassette 2.

For the meaning of the other elements designated in the figures, reference is made to the explanation of reference symbols in list form below.

The following first exemplary embodiment relates to a leak test on a disposable, here a blood cassette 2, which does not have a single-needle (SN) chamber or in which a single-needle chamber is separated from the extracorporeal blood circuit 1 by a single-needle valve 35 and stays. In this case, it is checked whether the blood cassette 2 is leakproof or sufficiently leakproof to the outside. Furthermore, with the door closed and pressed and with the blood cassette 2 inserted, it is checked whether a pressure can be built up and maintained in the extracorporeal blood circuit 1 (also: EB 1 for short, where 1 indicates the reference number). This test can be used in particular to check whether the extracorporeal blood circuit 1 (without patient hoses) is leak-tight, whether the two blood pump rollers are stationary and leaking, and/or whether there is sufficient compression to seal the flow paths and their branches in the blood cassette 2.

In addition, the function of the check valve 23 in the substituate channel can also be checked using the procedure described below, in particular the "closing" and "sealing" functions of the check valve 23 in the blood cassette 2.

To carry out the test, the blood cassette 2 is placed in the treatment device and pressed against the treatment device by closing a door thereof. The dialyzer or blood filter 19 is connected and filled on the disposable and hydraulic side. The extracorporeal blood circuit 1 is filled with liquid and largely free of air. The EB 1 is alarm-free, the blood system is active, the hydraulics are in a state of preparation, the dialysate flow is on. The arterial patient hose 8 and the venous patient hose 9 are both connected to the flushing port, not shown, via a T-piece.

At the beginning of the test of this embodiment of the invention, the automatic substituate connector 18b is in the connection position. The substituate supply line or branch is filled.

Valve V33 is closed. The hydraulics are switched to the so-called extended bypass (valves V24, V25 are de-energized). Valve V31 is open. The arterial patient hose clamp 6 and the venous patient hose clamp 7 are open (energized). The pre-dilution valve 13 and the post-dilution valve 14 are open, the single-needle valve 35 is closed.

If the pressure in the hydraulic system exceeds the predetermined pressure PTESTSTART_HYD (measured by means of a pressure sensor 37 arranged on the dialysis liquid supply line 31a), this is reduced with the aid of the substituate pump 17. To do this, V33 is opened and substituate is pumped until the hydraulic pressure (again measured by pressure sensor 37) has fallen below the pressure PTESTSTART_HYD. Substituate pump 17 is then stopped and V33 is closed again.

If the pressure in the hydraulic system does not exceed the predetermined pressure PTESTSTART_HYD, a check is made to determine whether the pressure in EB 1 exceeds the predetermined pressure PTESTSTART_EB (measured at pressure sensor 33b in the area of venous air separation chamber 21). If this is the case, this is relieved by opening valve V33 of the hydraulics; then the valve V33 is closed.

The blood pump rotor of the blood pump 11 is then positioned in such a way that only a first roller of the pump rotor is in engagement with the extracorporeal blood circuit 1 . Then both the arterial patient hose clamp 6 and the venous patient hose clamp 7 are closed and a predetermined waiting time PRESSURE COMPENSATION TIME is awaited for the pressure to equalize, and the arterial starting pressure (measured by the pressure sensor 33a of the arterial blood line) is noted to determine the roller standstill leakage.

With the substituate pump 17 liquid is conveyed into the EB 1 by means of a predetermined flow SUBSTITUATE PUMP: FLOW. First, the pre-filter pressure sensor 33c checks whether a test pressure PRUEFDRUCK can be built up in EB 1 within a defined time interval TIMEOUT.

If this is the case, after this intermediate test has been passed, the substituate pump 17 is stopped. After that, an appropriate time PRESSURE EVALUATION TIME is allowed to build up a static pressure. Is during the If the pressure has fallen below the minimum test pressure MIN TEST PRESSURE during the pressure equalization phase, the test is aborted with an error.

Otherwise, the test step that now follows is carried out for the second roller of the pump rotor, which differs from the first roller. The pressure drop is determined within a defined period of time TESTTIME. The absolute pressure change is considered, whereby this must not exceed a maximum value MAXIMUM PRESSURE DROP.

In contrast, when testing the first roll, a period of time TESTTIME is awaited without the pressure drop being evaluated.

After passing the test, the arterial pressure increase is evaluated. If this exceeds the specified pressure drop MAXIMUM STANDSTILL LEAKAGE, the occlusion is not complete.

The following test step is only performed for the first pulley of the pump rotor. It is tested whether the check valve 23 in the substituate channel closes and seals.

The previously built up test pressure is retained. The substituate pump 17 is used to deliver backwards with the aim of delivering a maximum delivery volume, and at the same time the absolute pressure drop, measured at the pressure sensor 33c, is evaluated. This must not exceed a maximum value MAXIMUM PRESSURE CHANGE or its amount. At the same time, the pressure in the blood cassette 2 must not increase (if this is the case, the substituate pump 17 rotates in the wrong direction).

Since the compartment between the check valve 23 and the adjacent substituate pump 17 is very small (<3 ml), the volume that can be conveyed by the substituate pump 17 is usually limited. If the check valve 23 does not close, the volume delivered depends on the maximum permissible pressure change MAXIMUM PRESSURE CHANGE. For a specific type of extracorporeal blood circuit 1 (in an air-free system), a pressure drop of 50 mbar corresponds approximately to a leakage of 250 μl.

In order to reduce the pressure in the EB 1, the arterial patient hose clamp 6, the venous patient hose clamp 7 and the valve V33 are energized.

The entire test is repeated for the other role of the blood pump rotor. To do this, first wait for the pressure in EB 1 to drop (PRESSURE EVALUATION TIME), then close the flushing port and continue with the step of positioning the blood pump rotor.

In the event of an error, the substituate pump 17 is stopped and the pressure in the EB 1 is reduced by opening the patient's venous hose clamp 7 and energizing the hydraulic valves V33, V28 and V19.

Tests by the applicant have shown that a leakage in the range of 5.5 ml/min to the outside or into the SN chamber can be detected by means of this test. Furthermore, it may be possible to detect non-compression and half-compression of the blood cassette 2 .

If the test is not passed, a one-time repetition is provided in some embodiments according to the invention. For safety reasons, it can be provided that the patient can only be treated after the test has been passed.

If the test is not passed, it may be necessary to dismantle the tested blood cassette 2 and exchange it for a new blood cassette 2 . The new blood cassette 2 is refilled and rinsed.

Examples of default values for the above parameters are given in the following parameter table (Table 1): Table 1 subtest parameter Unit value general parameters PRESSURE BALANCE TIME ms 2000 SUBSTITUTE PUMP: RIVER ml min ^-1 500 PTESTSTART_EB mbar 67 PTESTSTART_HYD mbar 333 "Build up pressure" TEST PRESSURE mbar 1400 MIN TEST PRESSURE mbar 1250 TIME-OUT ms 15000 "leak test" TESTTIME ms 5000 MAXIMUM PRESSURE DROP mbar 73 MAXIMUM STANDSTILL LEAKAGE mbar 400 "Check valve 23" MAX DELIVERY VOLUME ml 5 MAXIMUM PRESSURE CHANGE mbar 20

Errors encountered in this test and suggestions for correcting them are shown in the following error table (Table 2): Table 2 subtest Mistake "Build up pressure" TIMEOUT exceeded → SN valve 35 open → Disposable not fully pressed "leak test" MAXIMUM PRESSURE DROP exceeded → Disposable leaking MAX STANDSTILL LEAKAGE exceeded → Roller incompletely engaged "Check valve 23" MAXIMUM PRESSURE CHANGE exceeded → Non-return valve 23 not tight or → Substituate pump 17 rotates forward

With the test of this embodiment, a z. B. due to insufficient compression leaking blood cassette 2 can be detected.

A leakage sensor can also be provided to detect additional or other leakages.

The second embodiment according to the invention relates to a test for checking the tightness of the substituate connection. This test checks whether the substituate connection (automatic substituate connector 18b (ASK) with substituate port 18a) is leakproof to the outside. In addition, the closure of the disposable is checked for continuity.

For this purpose, the blood cassette 2 is placed in the treatment device and pressed. The rollers of the substituate rotor are extended. The hydraulics are available. The automatic substituate connector 18b connects. After the blood cassette 2 has been connected, a pressure maintenance test is carried out by means of the hydraulic system.

Using this test, it is possible to detect an outward leakage in the area of the automatic substituate connector 18b in the range of 1 ml/min (corresponds to about 500 ml/treatment). In addition, it is possible to determine that an online connection in the blood cassette 2 has been closed.

In some embodiments according to the invention, treatment of the patient is not possible without a passed test. This can be repeated as often as you like. Alternatively, the blood cassette 2 is dismantled and exchanged for another blood cassette.

With the pressure-controlled filling program of the balance chamber, pressure is built up in the area of the pressure sensor 37 against the stationary substituate pump 17 when the substituate connector is connected and valve V31 is open. During a holding phase, this pressure may only drop within certain limits. In order to keep the escape of liquid low in the event of a grossly leaking connection, a preliminary test with low pressure is carried out in certain embodiments according to the invention.

In addition, the continuity between the hydraulics of the treatment device 4 and the substituate pump 17 is tested by expecting a pressure drop at the pressure sensor 37 as a result of moving or operating the substituate pump 17 .

At or before the start of the test, valve V31 and valve V24 are closed.

The addition point 13, like the addition point 14, is closed. The substituate pump 17 stops.

To start the test, a pressure-controlled filling program is started. A pressure value LOW PRESSURE LIMITS is requested. A TIMEOUT period of e.g. B. Waited 2 s during which a minimum pressure should have LOW PRESSURE LIMITS built up or maintained as part of a quick test. If this is not the case, not even within the waiting time TIMEOUT, then a problem with the hydraulics can be assumed.

The pressure measured by the pressure sensor 37 can be stored.

Subsequently, the valve V31 several times, z. B. three times (NV31), closed for a short time and reopened after a waiting time TV31. Meanwhile, a predetermined minimum pressure MIN PRESSURE must be maintained. Thereafter, V31 remains open to see if a predetermined pressure drop is maintained. If the predetermined maximum pressure drop MAXDRUCKABALL is exceeded, or if a predetermined minimum pressure MINDRUCK is not maintained, then a fault can be assumed; the test is then not passed, possibly because the connection to the substituate port 18a is leaking. In this test section, the minimum hydraulic pressure can be monitored to rule out a pressure build-up caused by the filling program.

After this quick test, a pressure-controlled filling program with a pressure HIGH PRESSURE LIMITS is started for a permeability test to build up pressure. If a predetermined pressure PRUEFDRUCK_HIGH is measured at the pressure sensor 37, the process continues. If the minimum pressure at the sensor 37 is not built up within a waiting time TEST PRESSURE TIMEOUT, although the hydraulic system is available, a fault can again be assumed, for example a grossly leaking substitute port 18a.

If, on the other hand, the expected minimum pressure is built up, a pressure-controlled filling program with low pressure limits LOW PRESSURE LIMITS is requested. After waiting for a waiting time PRESSURE COMPENSATION TIME, it must be checked whether the pressure measured by the pressure sensor 37 falls below the expected minimum pressure MINTEST PRESSURE. If this is the case, an error can be assumed, which may be due to a leaky connection to the substituate port 18a.

After a dead time PRESSURE COMPENSATION TIME the process continues.

The pressure measured by the pressure sensor 37 can be stored.

In a next step, the valve for the addition point 14 is opened to wet the substituate pump and to test the blood cassette 2 for its permeability. The valve for the addition point 13 remains closed. The substituate pump 17 is advanced by a predetermined volume SPVOLUMEN. A low flow SUBSTITUTE PUMP: FLOW can be set for this purpose.

If the pressure drop then determined by means of the pressure sensor 37 remains below an expected pressure drop or below a minimum pressure drop MIN PRESSURE DROP, then a fault is inferred; the connection to the substituate port 18a may not be continuous.

Otherwise, the method advances to a leak test. For this purpose, the valve of the addition point 14 is closed.

A pressure-controlled filling program with a pressure HIGH PRESSURE LIMITS can be switched, which in turn is used to check the connection to the substitute port 18a. After the waiting time TIMEOUT, during which a predetermined pressure PRUEFDRUCK_HIGH must be built up, otherwise a leaking connection to the substitute port 18a is assumed, the system switches to a pressure build-up as described above using a pressure-controlled filling program with low pressure limits. If, after a holding time MEASUREMENT INTERVAL, certain criteria such as pressure drop per second below a predetermined limit value MAXLEAKAGE are met, the test is considered to have been passed. Otherwise, or if a waiting time MAXHOLDTIME is exceeded, an error is assumed; the connection to the substituate port 18a may be leaking.

To determine the pressure value during the pressure maintenance phase, proceed as follows:
The pressure value is smoothed. Low-pass filtering with the smoothing factor GF = 0.93 is used here: $$\mathrm{WORTH}\_\mathrm{New}=\mathrm{WORTH}\_\mathrm{old}*\mathrm{GF}+\mathrm{MEASUREMENT}*\left(1-\mathrm{GF}\right)$$

This pressure value is updated in each slice; the check for falling below the maximum leakage rate takes place every 2 seconds.

Examples of default values for the above parameters are given in the following parameter table (Table 3): Table 3 subtest parameter Unit value general parameters PTESTSTART_HYD mbar 200 PRESSURE BALANCE TIME ms 2000 LOW PRESSURE LIMIT mbar 250 TEST PRESSURE_HIGH mbar 1100 "rapid test" TSWITCH TIME ms 300 QUICK TEST ms 1750 MAX PRESSURE DROP % 75 MIND PRESSURE mbar 67 TV31 ms 250 NV31 number 3 "Test of Permeability" MIN TEST PRESSURE mbar 1050 TIME-OUT ms 2000 SUBSTITUTE PUMP: RIVER ml min ^-1 250 SPVOLUME ml 12 LOW PRESSURE DROP mbar 133 "leak test" PROOF PRINT TIMEOUT ms 2000 MAX LEAKAGE RATE mbar/s ^-1 2, 67 MEASUREMENT INTERVAL s 2 MAX HOLD TIME s 25

Errors encountered in the present test and suggestions for their correction are shown in the following error table (Table 4): Table 4 subtest Mistake "rapid test" TIMEOUT exceeded → Test pressure could not be built up → Hydraulic problem MAX PRESSURE DROP exceeded or below MIN PRESSURE → Excessive pressure drop: connection to the ASK is grossly leaking "Test of Permeability" TIMEOUT exceeded → Connection to ASK grossly leaking → or hydraulic problem MIN TEST PRESSURE undershot → Connection to ASK grossly leaking MINIMUM PRESSURE DROP not reached → Inconsistent connection to ASK "leak test" TIMEOUT exceeded → Connection to ASK grossly leaking → or hydraulic problem the MAX LEAKAGE was not undercut during the HOLDING TIME → Connection ASK-Disposable leaking

The third embodiment relates to a tightness and functional test of the addition points 13 and 14 designed as phantom valves for substituate in pre-dilution and in post-dilution. It is checked whether the phantom valves open, close and seal, or whether pressure gradients can be built up and maintained when the phantom valves open or close. Possibly "hanging" or incorrectly closing phantom valves can be detected here. This test can be repeated as often as you like. If it is consistently failed, the test can be dismantled and a new disposable inserted. Alternatively, a service employee can be informed. In certain embodiments according to the invention, treatment of the patient is not possible without passing the test. This test can also be carried out if the valves or addition points are not designed as phantom valves but are of another type of valve.

To carry out this test, the blood cassette 2 is inserted and compressed as described above. The blood filter 19 is connected and filled on the disposable and hydraulic side. The extracorporeal blood circuit 1 is filled and largely free of air. The extracorporeal blood circuit 1 has preferably already passed the tightness test of the first embodiment.

The arterial patient hose 8 and the venous patient hose 9 are each connected to the flushing port via a T-piece.

At the beginning of the test, the hydraulics are placed in the extended bypass. At the same time, valves V31 and V33 are energized and the pressure-controlled filling program is started. Valve V32 is closed.

The valve of addition point 13 (pre-dilution) is opened, that of addition point 14 (post-dilution) and the single-needle valve 35 remain closed. The arterial patient hose clamp 6 and the venous patient hose clamp 7 are or remain closed.

If the pressure in the hydraulic system exceeds a predetermined pressure PTESTSTART_HYD (measured by means of pressure sensor 37), this is reduced with the aid of substituate pump 17 and a flow SUBSTITUATE PUMP: FLOW. The arterial patient hose clamp 6 and the venous patient hose clamp 7 can be opened for this. In any case, the valve V33 is opened and the substituate is pumped until the hydraulic pressure (measured by means of the pressure sensor 37) has fallen below the pressure PTESTSTART_HYD. Substituate pump 17 is then stopped and valve V33 is closed again.

If the pressure in the hydraulics does not exceed the predetermined pressure PTESTSTART_HYD (measured by pressure sensor 37), pressure sensor 33b is used to check whether the pressure measured in extracorporeal blood circuit 1 exceeds pressure PTESTSTART_EB (measured by venous pressure sensor 33b). If this is the case, this is relieved by opening valve V33 of the hydraulics; then the valve V33 is closed.

For testing, the target pressure PRUEFDRUCK is built up in the extracorporeal blood circuit 1 with the substituate pump 17 (SUBSTITUATE PUMP: FLOW), measured by the pressure sensor 33b. This should be reached within the waiting time PRESSURE BUILD-UP TIMEOUT. If no such pressure build-up is detected at the pressure sensor 33b, it is assumed that the valve of the feed point 13 does not open or that the single-needle valve 35 is open.

If there is no error, the addition point 13 is closed, with the substituate pump 17 continuing to run. Normally, the pressure in the extracorporeal blood circuit 1 does not change after waiting for a waiting time PRESSURE COMPENSATION TIME during the subsequent waiting time MEASUREMENT DURATION. If it nevertheless increases by a value greater than the pressure rise MAXIMUM PRESSURE RISE (measured using pressure sensor 33b), then a problem with the valve(s) of the addition point(s) 13 and/or 14 can be concluded.

If the intermediate test is passed, the substituate pump 17 is stopped and the pressure in the extracorporeal blood circuit 1 is reduced by opening the patient's venous clamp 7 and the addition point 13 and the waiting time PRESSURE COMPENSATION TIME is awaited.

Addition point 14 (post-dilution) is checked in the same way as that of addition point 13 (pre-dilution).

By opening the patient's venous hose clamp 7 and by stopping the substituate pump 17, the pressure in the extracorporeal blood circuit 1 is reduced for the last time.

In the event of an error, the pressure in the extracorporeal blood circuit 1 is reduced by opening the patient's venous hose clamp 7 and stopping the substituate pump 17 . Hemofiltration (HF) and hemodiafiltration (HDF) are then no longer possible.

Examples of default values for the above parameters are given in the following parameter table (Table 5): Table 5 subtest parameter Unit value General parameters PRESSURE BALANCE TIME ms 2000 SUBSTITUTE PUMP: RIVER ml min ^-1 100 PTESTSTART_EB mbar 67 PTESTSTART_HYD mbar 333 "Does valve 13 open?" TEST PRESSURE mbar 300 PRESSURE BUILD TIMEOUT ms 10000 "Is valve 13 closing? Valve 13 & valve 14 tight?" MAXIMUM PRESSURE RISE mbar 4 MEASUREMENT TIME ms 5000 "Does valve 14 open?" PRESSURE BUILD TIMEOUT ms 5000 TEST PRESSURE mbar 300

Errors encountered during this test and suggestions for their elimination are shown in the following error table (Table 6): Table 6 subtest Mistake "Does valve 13 open?" PRESSURE BUILD TIMEOUT exceeded → Valve 13 not open "Is valve 13 closing? Pressure increased by MAX Are valve 13 & valve 14 tight?" PRESSURE RISE → Valve 13 open → Valve 14 open → Valve 13 and/or valve 14 leaking "Does valve 14 open?" TEST PRESSURE not reached → Valve 14 not open

The fourth embodiment relates to a leak test for the single needle (SN) system. Test air is used to check whether the SN area is sealed to the outside.

For this test, the blood cassette 2 is inserted and pressed as described above. The single needle valve 35 is closed. It is checked whether, with the blood cassette 2 pressed, a pressure can be built up and maintained in the single-needle overpressure and underpressure compartment. SN system leaks of 500 ml/4 h and more can be detected.

If you fail the test, you can repeat it as often as you like. Alternatively, SN operation can be suppressed or prevented. As always, if the test fails, it can be repeated with a new disposable or the service can be informed.

In certain embodiments according to the invention, it is possible to combine this test with the functional test “SN pneumatic system” of the sixth embodiment.

The amount of liquid or its volume in the single-needle chamber is a maximum of 10 ml.

At the start of the test, the bypass valve 352 is de-energized (=open) and the vent valve 354 is energized (=open). The single needle valve 35 is closed. The single-needle system, including the SN tank, is thus brought to ambient pressure. This is the case when the SN pressure sensors 358 and 356 are at most one value OFFSET_MAX deviate from zero. This process must be completed after a waiting time TIMEOUT_INIT. Otherwise, the initial conditions could not be established, for example because vent valve 354 and/or bypass valve 352 do not open correctly.

$$M_{\mathit{ges}}=m_{\mathit{over}}+m_{\mathit{under}}=\frac{p_{\mathit{over}}\cdot V_{\mathit{over}}+p_{\mathit{under}}\cdot V_{\mathit{under}}}{T\cdot R_S}$$

• R_S = spez. Gaskonstante für trockene $\mathrm{Luft}=287\frac{J}{\mathit{kg}\cdot K}$
  
• p_over = Druck im Überdruckkompartiment (abs.) = gemessen mit Drucksensor 358
• p_under = Druck im Unterdruckkompartiment (abs.) = gemessen mit Drucksensor 356
• V_over = Volumen des Überdruckkompartiments = 87 ml
• V_under = Volumen des Unterdruckkompartiments = 308 ml
• T = Umgebungstemperatur (K) = gemessen mit Temperatursensor 362

For the leak test, the vent valve 354 and the bypass valve 352 are closed to build up a test pressure. Then there is a waiting time PRESSURE COMPENSATION_TIME_SHORT and then the take-off mass (total air mass) is calculated in the single-needle system using the following formula (equation for ideal gases, isotherm): $$\begin{array}{cc}m=\frac{\mathit{pv}}{R_{S}T}& m\left[\mathit{\mu g}\right]=\frac{p\left[\mathit{father}\right]\cdot V\left[{\mathit{mm}}^3\right]}{R_S\left[\frac{J}{\mathit{kg}\cdot K}\right]\cdot T\left[K\right]}\end{array}$$

$$M_{\mathit{total}}=m_{\mathit{over}}+m_{\mathit{under}}=\frac{p_{\mathit{over}}\cdot V_{\mathit{over}}+p_{\mathit{under}}\cdot V_{\mathit{under}}}{T\cdot R_S}$$

• R _S = spec. Gas constant for dry $\mathrm{Air}=287\frac{J}{\mathit{kg}\cdot K}$
  
• p _over = pressure in the overpressure compartment (abs.) = measured with pressure sensor 358
• p _under = pressure in the underpressure compartment (abs.) = measured with pressure sensor 356
• V _over = volume of overpressure compartment = 87 ml
• V _under = volume of the vacuum compartment = 308 ml
• T = ambient temperature (K) = measured with temperature sensor 362

The SN compressor 350 is started with a voltage SN COMPRESSOR: VOLTAGE, which is equivalent to a compressor rate SN COMPRESSOR: RATE. In the closed system, a pressure (measured by the pressure sensor 358) equal to or above a test pressure TEST PRESSURE is thereby built up within a waiting time TIMEOUT_DP. If this pressure has been built up successfully, the SN compressor 350 is stopped and the waiting time PRESSURE COMPENSATION_TIME_LONG is awaited. The air mass (M_ges(tStart)) in the SN system is then calculated after the pressure build-up and compared with the take-off mass. The mass difference M_ges_0 - M_ges(tStart) must not fall below a value DM_BUILD_FALL and not exceed a value DM_BUILD_RISE. Otherwise the mass change in the system during the pressure build-up is too pronounced.

For the leakage measurement, the air mass in the system (M_ges_(tEnd)) is recalculated after a waiting period MEASUREMENT DURATION and compared with the starting mass at the beginning of the pressure maintenance test (M_ges(tStart)). The amount of the mass difference M_ges (tStart) - M_ges (tEnd) must not exceed a value DM_TEST_MAX. If it exceeds this value, the mass change in the system during the pressure hold test is too high.

An assessment of the "loss of mass" and no direct assessment of the pressure change in the respective compartments can be carried out due to a permissible (because it cannot be ruled out) slight leakage of the SN compressor from the overpressure into the underpressure compartment.

At the end of the test, the bypass valve 352 is de-energized and the single-needle system is ventilated by energizing the vent valve 354 .

Examples of default values for the above parameters are given in the following parameter table (Table 7): Table 7 subtest parameter Unit value general parameters PRESSURE COMPENSATION_TIME_LONG s 5 PRESSURE COMPENSATION_TIME_SHORT s 1 "Create initial conditions" OFFSET_MAX mbar 47 TIMEOUT_INIT s 10 "Test pressure build-up for leak testing" SN COMPRESSOR: VOLTAGE V 4 TEST PRESSURE mbar 950 TIMEOUT_DP s 60 "Mass change after pressure build-up" DM_BUILD_FALL mg -15 DM_BUILD_RISE mg 10 "Mass change in pressure maintenance phase" MEASUREMENT TIME s 15 DM_TEST_MAX mg 1.5

Errors encountered in this test and suggestions for correcting them are shown in the following error table (Table 8): Table 8 subtest Mistake "Create initial conditions" TIMEOUT_INIT reached → Valve 354 does not open (properly) or → Bypass valve 352 does not open (properly) or → Offset of the pressure sensors too large (sensors defective) "Test pressure build-up for leak testing" TIMEOUT_DP reached → the test pressure could not be built up → Valve 354 not closed/leaking or → Bypass valve 352 not closed or → Single needle valve 35 not closed "Mass change after pressure build-up" DM_BUILD_FALL reached → the mass change in the system during the pressure build-up was too high → Valve 354 leaking or → Single needle valve 35 not closed DM_BUILD_RISE reached → the mass change in the system during the pressure build-up was too high → Tank grossly leaking or → Level in the SN chamber too high "Mass change in DM_TEST_MAX exceeded pressure maintenance phase" → Mass change in the system during the pressure hold test too high → Tank leaking and/or → SN chamber leaking

The fifth embodiment relates to a functional test of the check valve 23 in the substituate channel. This test can be part of the leak test of the first embodiment discussed above, as described for the first embodiment. It is checked whether the check valve 23 in the substituate channel is functional. A pressure previously built up in the EB 1 must not drop despite the substituate pump 17 running backwards. This test advantageously avoids the migration of blood into the substituate channel and the contamination of the automatic substituate connector 18b (an on-line connector) with blood.

If the test is not passed, it can be repeated once. Treatment of the patient is only possible if the test is passed.

For details on this method, which can also be carried out separately from other tests, reference is made to its description above.

The sixth embodiment relates to a functional test of the single needle (SN) pneumatic system.

This test checks whether the single-needle compressor is running, whether the pneumatic valves are switching, the pressure sensors function and whether the pneumatic system on the machine side is tight.

For this purpose, a pressure gradient is built up in the single-needle system when the disposable is inserted and pressed, and if necessary after the T1 test has been successfully completed. It is checked whether the pressure gradient is maintained within a specified time or at least does not drop more than allowed.

If this test is not passed, specific embodiments according to the invention provide for preventing single-needle operation.

If a blood alarm occurs during the test of any embodiment of the present invention, the current test step is aborted. After the alarm has been eliminated, some embodiments according to the invention provide for the interrupted test to be repeated automatically.

If an error message of the test step is present when the alarm occurs, then in some embodiments according to the invention this is automatically deleted when the test step is repeated.

If no substitute is available (conductivity/temperature alarm), then in certain embodiments the test or partial test is also aborted and then triggered again.

If the conductivity LF is outside a tolerance range, no substituate is provided in some embodiments of the invention.

If the level in the venous chamber falls during a test, the test is terminated in certain embodiments of the invention. An exception to this can be the leak test for the substituate connection.

If one of the functional tests fails, a confirmable alarm is generated in the event that an arterial optical detector (OD) indicates "dark" (= blood enters the extracorporeal blood circuit). If an OD (venous) arranged in the venous section shows "dark", the disposable is to be dismantled.

The tests and sub-tests of the embodiments presented above can be combined with one another at will, unless and to the extent that this is not recognized as technically impossible by a person skilled in the art.

An appropriately programmed or configured function test monitor is used to ensure that the relevant function tests are carried out before the start of each treatment and that errors are detected. This monitors the performance of the function tests and checks their results.

The inventive method includes in some embodiments of the invention in addition to the actual - z. B. as described above - function tests also determine the system offset of the fistula pressure sensors.

If the transition of the arterial optical detector (OD) to "dark" (= blood enters the extracorporeal blood circuit) recognizes that a function test has not been carried out or has not been carried out successfully, then in some Embodiments according to the invention output a corresponding blood alarm. If necessary, this can be reset in order to be able to bridge any short-term disturbances of the arterial OD caused by air bubbles or the like. However, this is not always intended. The bridging time can be 0.25 s, for example. If the arterial OD remains dark, no treatment is possible in certain embodiments of the invention.

In addition, if a functional test fails when the venous OD detects blood, an unconfirmed blood alarm is generated, forcing a system shutdown.

In particular, the procedure for monitoring the SN system function test may deviate from this. If this is recognized as not passed (or not executed) when the venous OD changes to "dark", then SN treatment is prevented by setting a corresponding variable (e.g. E2_SN_Enable to SECURE_FALSE). In some embodiments according to the invention, no check takes place when the arterial OD changes to “dark”.

If test errors occur, status and error variables can be set. Entries in error tables or logs can be generated independently of this. In both cases, the test carried out in each case and the error condition can be stored, in particular in a readable form.

If the function tests are not completed when the target flushing volume is reached, then the target flushing volume is in some embodiments according to the invention automatically increased by 50 ml. A corresponding message can be issued.

Appropriate messages can be output if function tests pass and/or fail.

Reference List

1

extracorporeal blood circuit

2

blood cassette

3

first fluid guide of the automatic substituate connector 18b

4

treatment device

5

second fluid guide of the automatic substituate connector 18b

6

arterial patient hose clamp

7

venous patient hose clamp

8th

arterial patient hose or arterial blood line

9

venous patient hose or venous blood line

10

third fluid guide of the automatic substituate connector 18b

11

blood pump

11'

Braking device of the blood pump

13

Addition point for substituate liquid (predilution)

14

Addition point for substituate liquid (post-dilution)

15

arterial air blood detector

17

substituate pump

17'

Braking device of the substituate pump

18a

automatic substitute port

18b

automatic substituate connector

19

blood filter

19a

blood chamber

19b

dialysate chamber

21

venous air separation chamber

23

Substituate channel check valve

25

venous air blood detector

26

compressed air source

27

Blood filter blood inlet 19

28

Control and/or regulation device

29

Blood outlet of the blood filter 19

31a

dialysis liquid supply line

31b

dialysate drain line

33a, b

pressure sensors

33c

pre-filter pressure sensor

35

Single needle valve

37

pressure sensor

40

hydraulic balance chamber

41

Blood filter dialysate inlet 19

43

Blood filter dialysate outlet 19

45

drain line

47

sterile air supply

V19

Dialysate drain line valve 31b

V24

Dialysis liquid inlet line valve 31a

V25

Dialysate drain line valve 31b

V28

Drain line valve 45

V31

Valve of the first fluid line 3 of the automatic substituate connector 18b

V32

Valve of the second fluid line 5 of the automatic substituate connector 18b

V33

first valve of drain line 45

V42

Sterile air supply valve 47

V43

Valve of the third fluid line 10 of the automatic substituate connector 18b

H33

flush port

P03

ultrafiltration pump

100

air distribution panel

200

pneumatic unit

300

Single needle unit

301

Ventilation

350

Single needle compressor

352

bypass valve

354

vent valve

356

pressure sensor

358

SN line pressure sensor

360

absolute pressure sensor

362

Temperature sensor in the SN pressure vessel

370

Connector, connects the single-needle unit 300 to the single-needle chamber of the blood cassette 2

Claims (14)

1. A method for checking at least one function of a medical functional device, which is inserted into a medical treatment apparatus (4) and connected and pressed thereto, and/or one function of this treatment apparatus (4), wherein at least one fluid communication is established between a hydraulic device or a pneumatic unit (200) of the treatment apparatus (4) and the functional device, the method comprising the steps of:

   - building up a pressure by means of the hydraulic device or a pneumatic unit (200) within the fluid communication;

   - measuring a pressure rise within the fluid communication,

   characterized in that at least one function of a valve for an addition point (13) for substituate in pre-dilution and of a valve for an addition point (14) for substituate in post-dilution is tested;
   and in that the method comprises the step of:

   - making a statement about the checked function of the functional device based on a comparison of the measured pressure rise with previously stored values, threshold values, ranges or changes,
   wherein the addition points (13, 14) or the valves for the addition points (13, 14) for substituate liquid in pre-dilution or post-dilution, are designed as phantom valves, respectively.
2. The method according to claim 1, wherein the step of:

   - building up a pressure by means of the hydraulic device or a pneumatic unit (200) within the fluid communication

   is only executed if no functional deviation was detected during a prior application of a pre-pressure which is lower than the pressure to be built up.
3. The method according to anyone of the preceding claims, comprising the step of:

   - building up the pressure by means of a substituate pump (17) of the treatment apparatus (4).
4. The method according to claim 1 or 2, comprising the step of:

   - building up the pressure against the substituate pump (17) at standstill.
5. The method according to anyone of the preceding claims, comprising the step of:

   - detecting a pressure rise within the fluid communication;

   - determining a continuity and/or tightness of the fluid communication or of the functional device based on a comparison of the detected pressure rise with previously stored values, thresholds, ranges or changes.
6. The method according to anyone of the preceding claims, wherein at least one function, in particular the opening, the closing or the sealing, of at least one of the following components is tested:

   - a single-needle valve (35);

   - a non-return valve (23) in the substituate channel; and/or

   - an automatic substituate connector (18b).
7. The method according to anyone of the preceding claims, comprising the step of:

   - blocking treatment modalities and/or restricting treatment parameters of the treatment method, taking into account a result of the check of at least one function of the medical functional device and/or of the treatment apparatus (4), wherein the result was obtained by means of the present method.
8. A detection device programmed and/or configured to execute or initiate a method according to anyone of claims 1 to 7.
9. The detection device according to claim 8, comprising at least one display device for displaying a result of the execution of the method according to anyone of claims 1 to 7.
10. The detection device according to claim 8 or 9, comprising at least one alarm device for outputting an alarm, wherein the alarm device is provided for outputting an alarm in the event that the result of the execution of the method according to anyone of claims 1 to 7 is not within a predetermined range or a predetermined range of values.
11. The detection device according to anyone of claim 8 to 10, which is programmed and/or configured to act on the treatment apparatus (4) such that at least one treatment option, for which the checked functional device is usable due to its construction, and/or the treatment under predetermined treatment parameters, cannot be performed by means of the concrete checked functional device, if a malfunction of the functional device and/or of the treatment apparatus (4), or of a component thereof, respectively, has been detected.
12. A medical treatment apparatus, which comprises at least one detection device according to anyone of claims 8 to 11 and/or is in signal transmission or is connected for signal transmission therewith.
13. The medical treatment apparatus according to claim 12, which is designed as a blood treatment apparatus, in particular as an apparatus for apheresis or dialysis, again in particular for hemodialysis, hemofiltration, hemodiafiltration.
14. A computer program product with a program code stored on a machine-readable medium for initiating the mechanical steps of the method based on the method according to anyone of claims 1 to 7, when the computer program product runs on a detection device according to claims 8 to 11.

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